Hearts goalkeeper Zdenek Zlamal appeared to be struck by a Hibs fan as he went to retrieve the ball, and later claimed he was “punched in the face” by a supporter, while Neil Lennon was hit with a coin thrown from the main stand after he celebrated a late goal for Hearts being ruled out for offside.

On more than one occasion, fans managed to get onto the pitch. There were five arrests at the game, while police have confirmed they are probing the incidents involving Lennon and Zlamal.

Maxwell condemned the “actions of a minority of supporters”, warning that they had “crossed the line in what anyone would consider to be acceptable conduct”.

He added: “In addition to the well-documented incidents that saw Neil Lennon and Zdenek Zlamal on the receiving end of cowardly attacks from the stands, I am sorry to confirm that two of our match officials were also struck by objects.

“Knowing the clubs involved as I do, I know no stone will be left unturned - in conjunction with the relative authorities - to identify the individuals responsible and ensure the relevant steps are taken to leave them in no doubt that such actions will not be tolerated by Scottish football.

“Beyond that, we cannot accept that two assistant referees simply carrying out their duties are put in that position and I would like to commend their commitment and professionalism in seeing the game through to its conclusion.